If you're of a certain age, you might remember a time when The Simpsons was one of the funniest and most-watched shows on TV. At its peak strength in the early-to-late 90s, the cartoon was packed with witty dialogue, scathing social satire and brilliant sight gags. Then it fell into decline, but for reasons I failed to understand for a long time, it was allowed to continue despite having drifted into irrelevance. It's still on TV, but it's not what it was 20 years ago.

The reason it stayed around so long is this: Matt Groening didn't just create a cartoon, he created a merchandising empire. The Simpsons never met a product they couldn't sell, including clothing, school supplies, books, toys, arcade games (okay, that was pretty awesome) and amusement park rides. Why is The Simpsons starting a 24th season this fall? Because people are still getting paid, that's why.

Here's one example from the good old days: this ad for the 1993 Toyota Corolla. Apparently, driving The Homer didn't work out for Homer Simpson, so he decided to invest in something a bit more beige.

Grandpa Abe is pissed at how much money Homer spent, until Homer explains the tremendous value behind a Corolla – which gets Grandpa so fired up he immediately takes the kids for a spin and leaves Homer in the dust. Calm down, Grandpa, it's just a Corolla, and not even an AE86 or anything.